Datasheet
620
• Bits 13 and 12—PB6 Mode (PB6MD1 and PB6MD0): PB6MD1 and PB6MD0 select the
function of the PB6/IRQ4/A18/BACK pin.
Bit 13:
PB6MD1
Bit 12:
PB6MD0 Description
0 0 General input/output (PB6) (initial value)
1 Interrupt request input (IRQ4)
1 0 Address output (A18) (PB6 in single chip mode)
1 Bus right request output (BACK) (PB6 in single chip mode)
• Bits 11 and 10—PB5 Mode (PB5MD1 and PB5MD0): PB5MD1 and PB5MD0 select the
function of the PB5/IRQ3/POE3/RDWR pin.
Bit 11:
PB5MD1
Bit 10:
PB5MD0 Description
0 0 General input/output (PB5) (initial value)
1 Interrupt request input (IRQ3)
1 0 Port output enable (POE3)
1 Read/write output (RDWR)
• Bits 9 and 8—PB4 Mode (PB4MD1 and PB4MD0): PB4MD1 and PB4MD0 select the
function of the PB4/IRQ2/POE2/CASH pin.
Bit 9: PB4MD1 Bit 8: PB4MD0 Description
0 0 General input/output (PB4) (initial value)
1 Interrupt request input (IRQ2)
1 0 Port output enable (POE2)
1 Column address strobe (CASH) (PB4 in single chip mode)
• Bits 7 and 6—PB3 Mode (PB3MD1 and PB3MD0): PB3MD1 and PB3MD0 select the
function of the PB3/IRQ1/POE1/CASL pin.
Bit 7: PB3MD1 Bit 6: PB3MD0 Description
0 0 General input/output (PB3) (initial value)
1 Interrupt request input (IRQ1)
1 0 Port output enable (POE1)
1 Column address strobe (CASL) (PB3 in single chip mode)